Syringes are well known in the medical and surgical field, and have been used for many years for injecting drugs and other substances into patients. Such medications are available in multidose vials and single dose vials. However, because of cost considerations, the multidose vial is much more economical. If a patient is only receiving a single medication in a given injection, the use of a multiple-dose vial does not create problems, since a sterile syringe can be used to draw the necessary medication from the vial without contamination of the remaining medication. However, in situations where a patient is to receive multiple medications in a single injection, the use of multiple-dose vials becomes a problem. If a first medication is drawn into a syringe from a multiple dose vial, insertion of this syringe into a second such vial will contaminate the second vial with some of the first medication, or with other foreign substances. As a result, the use of multiple-dose vials has decreased substantially in the last several years, in favor of single-dose vials. This leads to an increase in expense to the patient, & practitioner, & institution as well as inefficient and uneconomical use of resources.
Despite the above problems, nothing appears to be available in the prior art which is capable of alleviating these problems. While syringes for storing and intermixing various ingredients are well known, none of these syringes are capable of receiving multiple medications from multiple-dose vials without contaminating at least one of the vials. For example, Schwartz U.S. Pat. No. 3,659,749 describes an intermixing syringe including means for isolating the storage of two components prior to their being mixed. In the disclosed invention, two isolated portions are provided within the syringe for receiving separate medicines. However, there is no suggestion of providing a separate port for injecting multiple medicines into the syringe itself.
Although resealable puncturable membranes have been utilized in the medical field previously, applicant is unaware of any use of such a membrane for sealing an auxiliary port in a syringe. Sheehan et al., U.S. Pat. No. 4,294,249 describes a swage-molded injection site which includes a self-sealing puncturable member of resilient material and a housing wherein the puncturable member is compressably confined. The injection site is designed for attachment to an intravenous assembly, but there is no suggestion of using such a member for sealing an auxiliary port in a syringe.
Accordingly, it is a primary object of this invention to increase the use of multiple-dose vials of medicines.
It is a further object of this invention to allow multiple medications to be injected in a single injection without contamination of the supply of such medications.
Yet another object of the invention is to economically provide a multimedication syringe which is simple to operate.
A still further object of the invention is to prevent contamination of multiple-dose vials while allowing multimedication injections.
Additional objects and advantages will be set forth in part in the description which follows, and in part, will be obvious from the description, or may be learned by practice of the invention.